Saladax, a privately held company, makes diagnostic products that measure levels of chemotherapeutic and antipsychotic drugs in blood.

Saladax Biomedical Inc., the Bethlehem-based biotech company, announced it signed an agreement to acquire exclusive patent rights for antipsychotic drug tests from Janssen Pharmaceutica NV in Belgium.

Janssen is part of the Janssen Pharmaceutical Companies of Johnson & Johnson.

Saladax, a privately held company, makes diagnostic products that measure levels of chemotherapeutic and antipsychotic drugs in blood.

In March, the company received clearance to sell two blood-based tests in Europe for the antipsychotic drugs risperidone and paliperidone.

The deal with Janssen will enable Saladax to expand its MyCare Psychiatry product line to include tests for four more commonly used antipsychotic medications: clozapine, olanzapine, quetiapine and total aripiprazole.

Saladax said it expects to receive regulatory clearance in Europe for those tests in the next quarter.

Financial terms of the deal were not disclosed.

With more than 18 million patients worldwide on antipsychotic medications, the potential diagnostic test market is worth an estimated $2 billion.

Managing patients who take antipsychotic drugs often is a challenge for physicians because an estimated 40 to 60 percent of those patients fail to take the medication.

Often, doctors are uncertain whether a lack of treatment response is from poor adherence or lack of efficacy, which could be from an insufficient dosage.

The Saladax tests provide clinicians with rapid, objective results so that timely clinical decisions can be made.

“We are very pleased to have signed this agreement and look forward to making this line of reagents the standard of care in the field of psychiatry,” Salvatore Salamone, CEO of Saladax, said in a statement.

The firm said it plans to submit the six antipsychotic drug tests to the United States Food and Drug Administration for approval.

Founded in 2014, Saladax is at Ben Franklin TechVentures at Lehigh University’s Mountaintop Campus.